LAUSR

Abstract The loss of porosity on heating above 500 °C for mesoporous silica materials such as SBA-15 limits some of their high temperature applications. 40% wt. CeO2 nanoparticles were encapsulated into SBA-15 in this study through molten cerium (III) nitrate impregnation and calcination. The thermal behavior of the ceria containing mesoporous silica was investigated and compared with pristine SBA-15 in the 300–1100 °C temperature range. While SBA-15 progressively loses pore volume, surface area and pore diameter on heating above 500 °C, the CeO2@SBA-15 material shows the same textural properties in the 300–700 °C temperature range. A slight 0.2 nm pore diameter decrease was noticed at 900 °C coupled with the sintering of the nanoconfined ceria, leading to loss of mesopore volume through pore blocking. Both pristine silica and the ceria nanocomposite become non-porous at 1100 °C. The thermal stability increase of the ceria containing SBA-15 was explained as a reinforcing effect of the ceria nanoparticles, which stops the temperature dependent mesopore radial constriction. The encapsulation of oxide nanoparticles into mesoporous SBA-15 silica is therefore a promising strategy for obtaining nanocomposites with increased thermal stability.